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Question
A bulb marked 12 V, 24 W operates on a 12 V battery for 20 minutes. Calculate:
- The current flowing through it, and
- The energy consumed.
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Solution
Given Power, P = 24 W
Voltage, V = 12 V
Current, I = ?
As power, P = VI
- I = `24/12
= 2 "A"` - Energy, E = P × t
E = 24 × 20 × 60 sec
E = 28800 J
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